This fan had a switch replacement and the wiring ended up not quite correct. The motor ran on Low and High. Unfortunately, after running on High for an extended period of time, the motor was found billowing smoke and running slowly. The result was this nasty mess!

In this video, I show how to test if the motor is actually burned out; as well as how to measure and determine which wires are which if you don't have an original wiring diagram or any other info to go on.

First, the carnage!

The first thing I noticed was the capacitor, all bloated and exploded.

So, I had to make some tests. This video goes over the testing and repairs.

Some pictures of the motor going back together.

The rotor and stator cleaned up. The burned smell was horrible! I had to use Zep Purple Power degreaser to clan the parts other than the winding. then for that winding, I cleaned it with spray solvent, then re-varnished it. Hoping that removed most of the stench, and then the rest will be permanently locked in by the new varnish!

Now, the stator is over the rotor. I have the new heat shrink over the lead wires, and the new string tying it all together. It's all coated in new varnish to bond it all together.

Now the rear housing is on. Put the capacitor, capacitor clip, and wiring junction part in place.

Thanks David. Showing how to safely test a motor you have no idea how to wire is very helpful.

You also inadvertently proved something else that has been discussed here in the past, about how important it is to use a larger voltage capacitor. John McComas has frequently suggested using a higher voltage capacitor than the normal ones sold for desk fans.

Andrew Block wrote: Thanks David. Showing how to safely test a motor you have no idea how to wire is very helpful.

You also inadvertently proved something else that has been discussed here in the past, about how important it is to use a larger voltage capacitor. John McComas has frequently suggested using a higher voltage capacitor than the normal ones sold for desk fans.
You're welcome. That is a good point about the capacitor voltage rating. Some of the ceiling fan and desk fan caps have a lower voltage rating of 250VAC. That could become a problem on this motor.

Maybe tomorrow I will have a chance to make a test of a small desk fan capacitor on it... :)